Re: SUREFIRE KNIVES!!
DarkLight and Benthead are right. Unless you're rather wealthy, carrying an expensive knife like these eventually becomes self-defeating; you're reluctant to cut anything for fear of damaging the edge, and you're always paranoid about losing the damn thing.
I had a cherry Emerson CQC-6 that was the envy of my knife-aware colleagues. I was VERY hesitant to use it, and when I considered employing a dummy cord, I realized I had gone over the precipice. I went back to $50 Spydercos and have been happy; and not afraid to cut things that need cutting. /ubbthreads/images/graemlins/grin.gif
Aside from that, those SureFire designs look to be more eye candy than utilitarian. There are lots of exposed areas and acute angles; ingress avenues for crud and less-than-comfortable ergonomics.
Methinks SureFire should stick to flashlights. They do that well...